Define the Concept of ‘Theta’ in Options Pricing (Greeks)

Theta, often called the time decay of an option, measures the rate at which an option's price decreases as the time to expiration shortens, assuming all other factors remain constant. It is typically a negative value for both long Call and Put options, reflecting the loss of time value.

Theta accelerates as the option gets closer to expiration, particularly for At-the-Money options.